Abstract In this paper, a curvature sensor based on fiber ring laser with Sagnac loop is proposed and experimentally demonstrated. The Sagnac loop is inserted into a fiber ring laser used as the sensing element and the filter. The intracavity sensing is induced in the fiber laser with the filtering characteristic of the Sagnac loop modulated by the curvature. The intracavity sensing system is used to narrow the corresponding 3-dB band-width and enhance the resolution of the curvature sensor. With the intracavity intensity modulation method, the output power of the fiber ring laser sensor will change with an increase in curvature. The curvature range from 0 m−1 to 5.6865 m−1 has been measured and the highest curvature resolution of 6 × 10−8 m−1 is obtained. Based on the intracavity sensing system, the curvature resolution level has been enhanced from 10−4 m−1 to 10−8 m−1. The stability and measurement errors of the system are also studied and analyzed.

中文翻译：

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基于带 Sagnac 环的光纤环形激光器的曲率传感器

摘要 本文提出了一种基于萨格纳克环光纤环形激光器的曲率传感器，并进行了实验验证。Sagnac 环被插入到用作传感元件和滤波器的光纤环形激光器中。腔内传感是在光纤激光器中通过曲率调制的萨格纳克环的滤波特性引起的。腔内传感系统用于缩小相应的 3-dB 带宽并提高曲率传感器的分辨率。采用腔内强度调制方法，光纤环形激光传感器的输出功率会随着曲率的增加而变化。已测量曲率范围从0 m-1 到5.6865 m-1，并获得了6 × 10-8 m-1 的最高曲率分辨率。基于腔内传感系统，曲率分辨率水平从 10-4 m-1 提高到 10-8 m-1。还对系统的稳定性和测量误差进行了研究和分析。